from pathlib import Path

import cv2 as cv
import numpy as np


input_path = Path("input/scene.png")
output_path = Path("output/scene-affine.png")

image = cv.imread(str(input_path))
if image is None:
    raise SystemExit(f"Could not read {input_path}")

height, width = image.shape[:2]
source_points = np.float32([
    [0, 0],
    [width - 1, 0],
    [0, height - 1],
])
target_points = np.float32([
    [35, 20],
    [width - 45, 8],
    [75, height - 42],
])

matrix = cv.getAffineTransform(source_points, target_points)
warped = cv.warpAffine(
    image,
    matrix,
    (width, height),
    flags=cv.INTER_LINEAR,
    borderMode=cv.BORDER_REFLECT,
)

output_path.parent.mkdir(parents=True, exist_ok=True)
if not cv.imwrite(str(output_path), warped):
    raise SystemExit(f"Could not write {output_path}")

print(f"source shape: {image.shape}")
print("matrix:")
print(np.array2string(matrix, precision=3, suppress_small=True))
print(f"output shape: {warped.shape}")
print(f"wrote: {output_path}")